Hi Hon,
Nice to see you.
Spiro is regarded by most endos as less effective than crypto as an AA, although it doesn't have the side effect of causing an acute depression in some users. I was on spiro as it is available here and I was nervous of CA due to my chronic depression issues.
It can drastically reduce BP, which is why it was first marketed, the AA effect was found later.
I don't think it is regarded as a better AA than CA, but as an alternative for those who don't tolerate CA.